U.S. patent number 8,702,720 [Application Number 11/743,745] was granted by the patent office on 2014-04-22 for tassel tip wire guide.
This patent grant is currently assigned to Cook Medical Technologies LLC. The grantee listed for this patent is Douglas E. McLaren. Invention is credited to Douglas E. McLaren.
United States Patent |
8,702,720 |
McLaren |
April 22, 2014 |
**Please see images for:
( Certificate of Correction ) ** |
Tassel tip wire guide
Abstract
An improved wire guide and method for cannulating a bodily
lumen, such the biliary tree are provided for procedures such as
endoscopic retrograde cholangiopancreatography (ECRP). The wire
guide and cannulation method minimizes the potential for trauma to
the ducts while reducing the chances of disconnecting the wire
guide from newer access devices. Generally, the wire guide includes
an atraumatic tassel tip which is operable between delivery and
deployed configurations.
Inventors: |
McLaren; Douglas E. (Rancho
Murieta, CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
McLaren; Douglas E. |
Rancho Murieta |
CA |
US |
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Assignee: |
Cook Medical Technologies LLC
(Bloomington, IN)
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Family
ID: |
38662040 |
Appl.
No.: |
11/743,745 |
Filed: |
May 3, 2007 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20070260158 A1 |
Nov 8, 2007 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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60797100 |
May 3, 2006 |
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Current U.S.
Class: |
606/108;
604/164.01 |
Current CPC
Class: |
A61M
25/09 (20130101); A61M 2025/09175 (20130101) |
Current International
Class: |
A61F
11/00 (20060101) |
Field of
Search: |
;27/24.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Nguyen; Victor
Assistant Examiner: Everage; Kevin
Attorney, Agent or Firm: Brinks Gilson & Lione
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application
Ser. No. 60/797,100, filed on May 3, 2006, entitled "TASSEL TIP
WIRE GUIDE," the entire contents of which are incorporated herein
by reference.
Claims
The invention claimed is:
1. A wire guide for intracorporeal procedures, the wire guide
comprising: a main body having a distal end, the main body defining
a longitudinal axis, the distal end of the main body constructed of
a plurality of wires stranded together to form the main body,
wherein distal portions of the plurality of wires form the
plurality of strands of a tassel tip; and the tassel tip formed at
the distal end of the main body, the tassel tip defined by a
plurality of strands each having a connecting portion, middle
portion and a free end portions, the connecting portion connected
to the main body at a connection point, the middle portion located
between the connecting and free end portion, the tassel tip
operable between a delivery configuration and a deployed
configuration, the free end portions of the plurality of strands
positioned adjacent the longitudinal axis in the delivery
configuration, the free end portions of the plurality of strands
spaced radially from the longitudinal axis in the deployed
configuration, the plurality of strands moving away from the
longitudinal axis and the middle portions being curved to define
atraumatic peaks in the deployed configuration, the free end
portions being positioned distally relative to the middle portions
in the delivery configuration, the free end portions being
positioned proximal to the connection point and pointing proximally
in the deployed configuration.
2. The wire guide of claim 1, wherein the free end portions of the
plurality of strands are radially spaced apart a distance greater
than a diameter of the main body in the deployed configuration.
3. The wire guide of claim 1, wherein the free end portions of the
plurality of strands extend proximally alongside the outside of the
main body in the deployed configuration.
4. The wire guide of claim 1, wherein each of the plurality of
strands has a diameter about equal to or smaller than a radius of
the main body.
5. The wire guide of claim 1, wherein the plurality of strands are
formed of flexible material having sufficient strength to from an
umbrella shape in the deployed configuration.
6. The wire guide of claim 1, further comprising a hub at the
distal end of the main body, the hub fixedly banding together the
plurality of wires.
7. The wire guide of claim 1, wherein the plurality of strands
includes at least four strands.
8. The wire guide of claim 1, wherein the plurality of strands each
have a circular cross-sectional shape.
9. The wire guide of claim 1, wherein the plurality of strands each
have a non-circular cross-sectional shape.
10. The wire guide of claim 1, wherein the plurality of strands
retroflex in the deployed configuration to define an umbrella
shape.
11. The wire guide of claim 1, wherein the free end portions are
generally straight in the deployed configuration.
12. The wire guide of claim 1, wherein the plurality of strands
have sufficient flexibility such that of proximal movement of the
main body while the tassel tip is in the deployed configuration
intracorporeally, causes the strands to unroll and move back to the
delivery configuration.
13. A wire guide for intracorporeal procedures, the wire guide
comprising: a main body having a distal end, constructed of a
unitary solid wire, the main body defining a longitudinal axis; and
a tassel tip formed at the distal end of the main body, the tassel
tip defined by a plurality of strands each having a connecting
portion, middle portion and a free end portions, the connecting
portion connected to the main body, the middle portion located
between the connecting and free end portion, a distal portion of
the solid wire connected to the plurality of strands, wherein the
distal portion of the solid wire includes a plurality of channels
fixedly receiving a portion of the plurality of strands, the tassel
tip operable between a delivery configuration and a deployed
configuration, the free end portions of the plurality of strands
positioned adjacent the longitudinal axis in the delivery
configuration, the free end portions of the plurality of strands
spaced radially from the longitudinal axis in the deployed
configuration, the plurality of strands moving away from the
longitudinal axis and the middle portions being curved to define
atraumatic peaks in the deployed configuration, the free end
portions being positioned distally relative to the middle portions
in the delivery configuration, the free end portions being
positioned proximal to the middle portions in the deployed
configuration.
14. The wire guide of claim 13, wherein the plurality of strands
are unitarily and integrally formed with the main body, the solid
wire of the distal end having longitudinal cuts to define the
plurality of strands.
15. The wire guide of claim 14, wherein the strands include outer
surfaces having material deformations to improve their flexibility,
and smooth inner surfaces.
16. The wire guide of claim 14, wherein each strand has a
pre-shaped cross-section, and wherein an inner edge of each strand
is curved and includes a filet.
Description
FIELD OF THE INVENTION
The present invention relates generally to wire guides for
intracorporeal procedures, and more particularly relates to wire
guides for assisting in cannulation during endoscopic procedures
such as endoscopic retrograde cholangiopancreatography (ERCP).
BACKGROUND OF THE INVENTION
ERCP is a study of the ducts that drain the liver and pancreas.
Generally, the liver produces bile that is concentrated by the
gallbladder and delivered to the duodenum (upper small intestine)
via the common bile duct. The pancreatic duct joins the bile duct
at the papilla of Vater where they drain into the duodenum through
the sphincter of Oddi. ERCP generally includes cannulation of the
biliary tree (which includes the bile duct, pancreatic duct, and
hepatic ducts of the liver) by delivering a catheter through the
working channel of a duodenoscope and into the biliary tree. A
contrast medium is injected through the catheter to provide for
diagnosis of problems in the liver, gallbladder, biliary tree and
pancreas, such as gallstones, inflammatory strictures, leaks or
cancer. Exemplary ERCP catheters are described in U.S. Pat. Nos.
5,320,602 and 5,383,849.
A wire guide is often used to assist in navigation of the catheter
(or other endoscopic access devices such as sphinctertomes,
balloons, biopsy devices, stent delivery catheters, dilators, etc.)
through the sphincter of Oddi and into the biliary tree, often
referred to as cannulation. Wire guides may also be used for deep
cannulation of the biliary tree. Wire guides, however, carry the
risk of trauma to structured segments of the bile or pancreatic
ducts which can result in life-threatening infection, perforation
or pancreatitis. Additionally, with the advent of new access
devices permitting rapid exchange of multiple devices without the
need for traditional "over the wire" or "long wire" exchanges (see,
e.g., U.S. Pat. Pub. No. 2005/0059890, the disclosure of which is
hereby incorporated by reference in its entirety) there exists the
possibility for unintentional disconnection of the access device
and wire guide.
Accordingly, there exists a need for a wire guide that assists in
cannulation of the biliary or pancreatic ducts and minimizes the
potential for trauma to the ducts. At the same time, it would also
be desirable to reduce the chances of disconnection of the wire
guide from newer access devices providing rapid exchange.
BRIEF SUMMARY OF THE INVENTION
The present invention provides an improved wire guide and method
for cannulating a bodily lumen such the biliary tree. The wire
guide and cannulation method minimizes the potential for trauma to
the ducts while reducing the chances of disconnecting the wire
guide from newer access devices.
According to one embodiment constructed in accordance with the
teachings of the present invention, the wire guide includes the
main body having a distal end, and a tassel tip formed at the
distal end. The tassel tip is defined by a plurality of strands
having free end portions. The tassel tip is operable between a
delivery configuration and a deployed configuration. The free end
portions of the plurality of strands are positioned adjacent the
longitudinal axis in the delivery configuration, and are spaced
radially from the longitudinal axis in the deployed configuration.
The strands curve away from the longitudinal axis to define
atraumatic peaks in the deployed configuration.
According to more detailed aspects, each strand further includes a
connecting portion and a middle portion between the connecting
portion and the free end portion. The middle portion is curved in
the deployed configuration to define atraumatic peaks for safe
navigation of the wire guide. The free end portions are positioned
distally relative to the middle portions in the delivery
configuration, and the free end portions are positioned proximally
relative to the middle portions in the deployed configuration. The
free ends of the plurality of strands are radially spaced apart a
distance greater than a diameter of the main body, and thus form an
umbrella shape at the distal end. The plurality of strands
preferably extend proximally along side the outside of the main
body. The plurality of strands are formed of a flexible material
having sufficient strength to form the umbrella shape in the
deployed configuration.
According to still further aspects, the distal end of the main body
may be constructed of a plurality of wires or may be constructed of
a solid or tubular wire. When the distal end of the main body is
constructed of a plurality of wires, the distal portions of the
plurality of wires may be used to form the plurality of strands of
the tassel tip. A hub at the distal end of the main body is used to
band together the plurality of wires. When the distal end of the
main body is constructed as a solid wire, the distal portion
preferably includes a plurality of channels receiving a portion of
the plurality of strands to reduce the overall package size, or
alternatively the strands may be unitarily and integrally formed
from the solid wire.
According to another embodiment in accordance with the teachings of
the present invention, a method for performing cannulation of a
bodily lumen is provided. The method generally includes the steps
of coupling the above-described wire guide to an access device,
whereby the plurality of strands are contained within a passageway
of the access device. The wire guide is translated distally
relative to the access device, the distal movement of the tassel
tip causes it to take a deployed configuration wherein the middle
portion of each of the strands curves to define atraumatic peaks
for safe navigation of the wire guide within the bodily lumen.
Preferably, the bodily lumen is the biliary tree of a mammalian
patient, and the method further includes a step of placing a
duodenoscope into the duodenum of the patient. Here, the advancing
step includes passing the wire guide and access device as a unit
through a channel of the duodenoscope and through a sphincter of
Oddi leading to the biliary tree.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings incorporated in and forming a part of the
specification illustrate several aspects of the present invention,
and together with the description serve to explain the principles
of the invention. In the drawings:
FIG. 1 depicts a perspective view of a wire guide constructed in
accordance with the teaching of the present invention;
FIG. 2 depicts a cross-sectional view, taken from the side, of the
wire guide depicted in FIG. 1;
FIG. 3 depicts a cross-sectional view, taken about the line 3-3 of
FIG. 2;
FIG. 4 depicts a side view, partially in cross-section, of a
delivery configuration of the wire guide depicted in FIGS. 1-3;
FIG. 5 depicts a cross-sectional view of an alternate embodiment of
the wire guide depicted in FIGS. 1-4;
FIG. 6 depicts a cross-sectional view of yet another alternate
embodiment of the wire guide depicted in FIGS. 1-4;
FIG. 7 depicts a cross-sectional view, taken about the line 7-7 of
FIG. 6;
FIG. 8 depicts a schematic view, partially in cross-section, of the
wire guide of FIGS. 1-4 in the process of cannulating the biliary
tree;
FIG. 9 depicts a cross-sectional view of still yet another
alternate embodiment of the wire guide depicted in FIGS. 1-4;
FIG. 10 is a cross-sectional view taken about the line 10-10 of
FIG. 9;
FIG. 11 is a cross-sectional view of the wire guide depicted in
FIGS. 9-10 shown in a deployed configuration; and
FIG. 12 is a cross-sectional view of an alternate tip configuration
for the wire guide depicted in FIGS. 9-11.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the figures, FIG. 1 depicts a deployed configuration
of a wire guide 20 constructed in accordance with the teachings of
the present invention. The wire guide generally includes the main
body 22 having a distal end 24 which includes a tassel tip 30. The
tassel tip 30 is formed by a plurality of strands 32. Preferably
the number of strands 32 is greater than or equal to 3, and the
currently preferred configuration of four strands has been depicted
in the figures. Each of the strands 32 is constructed of a flexible
material that permits them to retroflex, i.e. curve away from a
longitudinal axis of the wire guide 20 and extend proximally to
form an umbrella or tassel shape as shown in FIG. 1. The length of
tassels 32 and their flexibility are selected to provide the
desired curvature having atraumatic peaks 34 to prevent damage to
the bodily structures being navigated.
The strands 32 may be hydrophilic and/or radiopaque. For example,
the strands 32 may be formed of a metal such as platinum, stainless
steel, or an alloy such as a superelastic alloy of nickel titanium,
and can further include a hydrophilic coating that can be formed of
a hydrophilic polymer such as polytetrafluorethylene (PTFE),
Teflon.TM., silicone, glycerin, modified polyurethanes or various
blends. Of course, the strands 32 can be formed of suitable
plastics such as polytetrafluorethylene (PTFE), polyethylene ether
ketone (PEEK), polyvinylchloride (PVC), polyamide including
Nylon.RTM., polyimide, polyurethane, polyethylene (high, medium or
low density), and elastomers such as Santoprene.RTM., the plastic
being selected (or combined with other materials) to provide the
desired properties noted above. The construction of the strands 32
exhibits a suitable balance between flexibility and strength to
form the depicted umbrella shape and define the atraumatic peaks
34. Preferably each strand 32 has a diameter less than or equal to
the radius of the main body 22, depending on material
selection.
As best seen in FIGS. 2 and 3, the main body 22 of the wire guide
includes a plurality of wires 26 disposed over a mandrel 28. It
will be recognized that the mandrel 28 may be dispensed with, and
the wires 26 may be stranded together such as by twisting or
braiding. Preferably, the number of wires 26 equals the number of
strands 32 of the tassel tip 30 such that the wires 26 may be used
to form the strands. As such, the distal end 24 of the main body 22
includes a hub 36 which is used to band the wires 26 together.
Distally from the hub 36, the wires 26 form the strands 32 which
are free to curve and extend proximally to define the atraumatic
peaks 34. Specifically, each strand 32 includes a connecting
portion 32a connected to the main body 22, a middle portion 32b
curving to form the atraumatic peaks 32b, and a free end portion
32c opposite the connecting portion 32a.
As shown in FIG. 4, a delivery configuration of the wire guide 20
has been depicted. As discussed in the Background section, the wire
guide 20 has particular application in cannulation of the biliary
tree during procedures such as ECRP, and thus may be placed at the
entrance of the biliary tree in conjunction with an access device.
The access device has been depicted as a simple cannula or catheter
40 in FIG. 4. The catheter 40 includes an internal passageway 42
that is sized to receive the wire guide 20 and permit translation
relative thereto. As such, the wire guide 20 may be translated
beyond the open distal end 44 of the catheter 40 whereby the
flexible nature of the strands 32 causes them to take their
deployed configuration depicted in FIG. 1. From the deployed
configuration, proximal translation of the wire guide 20 relative
to the catheter 40 will cause the catheter's distal end 44 to
impinge upon the inner curvature of the strands 32, which will
again cause them to extend distally as the wire guide 20 is
withdrawn into the passageway 42 of the catheter 40.
In the delivery configuration depicted in FIG. 4, the strands 32
extend distally to define a compact shape that is suitable for
being received within the passageway 42 of the catheter 40. That
is, the free end portions 32c of the strands 32 are positioned
adjacent to the longitudinal axis of the wire guide 20 and main
body 22 in the delivery configuration. In the deployed
configuration of FIGS. 1 and 2, the free end portions 32c are
spaced radially outwardly from the longitudinal axis of the wire
guide 20 and main body 22. It can also be seen in the figures that
the free end portions 32c are positioned distally relative to the
middle portions 32b in the delivery configuration (FIG. 4), and
then proximally relative to the middle portions 32b in the deployed
configuration (FIG. 2). That is, the strands 32 retroflex to define
the umbrella shape.
It will be recognized by those skilled in the art that the main
body 22 of the wire guide may take many forms, including multiple
wound wires or single wires which may be solid or tubular in form,
as well as combinations thereof (see, e.g., U.S. Pat. No.
5,243,996). For example, FIG. 5 depicts a wire guide 120 having a
main body 122 formed of a single solid wire. As with the previous
embodiment, the distal end 124 of the main body 122 includes a
tassel tip 130 formed by a plurality of strands 132 defining
atraumatic peaks 134. The plurality of strands 132 may be attached
to the distal end 124 by many fastening methods including
soldering, welding, adhesives or mechanical deformation. As
depicted, a hub 138 is used to band or crimp the plurality of
strands 132 to the distal end 124 of the main body 122.
Similarly, FIGS. 6 and 7 depict another embodiment of the wire
guide 220 which uses a solid wire main body 222. In this
embodiment, the distal end 224 of the main body 222 includes a
plurality of channels 238 sized to receive at least a portion of
the plurality of strands 232. As with the previous embodiments, the
strands 232 define an atraumatic peak 234 and are connected to the
distal end 222 through use of a hub 236 that is used to band the
strands 232 to the main body 222. It can be seen that the strands
232 have a generally circular cross-sectional shape, and thus the
channels 238 are circular or semi-circular. Here, a hydrophilic
coating 240 has been shown on both the main body 222 and each of
the plurality of strands 232. As noted above, a hydrophilic coating
may optionally be used with any embodiment of the present
invention.
Yet another embodiment of the wire guide 320 has been depicted in
FIGS. 9-11. A solid wire main body 222 is cut, such as by laser or
other material removal processes, to unitarily and integrally form
the plurality of strands 332. As best seen in FIG. 10, any number
of strands 332 may be formed, each having a pie-shaped
cross-section. As with the prior embodiments, the strands 332 are
structured to form a delivery configuration (FIG. 9) for
positioning within the passageway 342 of a delivery catheter 340.
It will also be seen in FIG. 12 that the distal ends 354 of each of
the strands 332, rather than each having a semi-spherical tip as
shown in FIG. 9, may together form a semi-spherical or
bullet-shaped tip in the delivery configuration.
In the deployed configuration of FIG. 11, the free ends of strands
332 move away from the longitudinal axis and retroflex (i.e. curve
and extend proximally) to define the atraumatic peaks 334 and
general umbrella shape. It will be recognized that the strands 332
may include grooves 350 or notches 352 or other material
deformations to improve the flexibility of the strands 332 and
their operability into the deployed configuration of FIG. 11.
Preferably, an inner edge 333 of each strand 332 is further formed
to be curved, such as by a filet, to define the atraumatic peaks
334 of each of the strands 332.
The present invention includes a method for performing cannulation
of a body lumen employing the wire guides as described above. With
reference to FIGS. 1, 4 and 8, the method generally comprises the
steps of coupling a wire guide 20 to an access device 40. In FIG.
4, the wire guide 20 is coupled to the catheter 40 by positioning
the wire guide 20, or at least its distal tassel tip 30, within the
internal passageway 42 of the catheter 40. The plurality of strands
32 extend distally and are contained within the passageway 42. The
wire guide 20 and access device 40 are advanced as a unit into the
bodily lumen, such as the common bile duct depicted in FIG. 8,
although this step may not be used depending on the particular body
structures being cannulized. The wire guide 20 may then be
translated distally relative to the access device 40, whereby the
distal movement of the tassel tip 30 causes it to take a deployed
configuration such as depicted in FIGS. 1 and 8.
When the bodily lumen is the bile duct 54, pancreatic duct 60, or
another portion of the biliary tree, the method may further include
the steps of placing a duodenoscope 50 into the duodenum 62 of the
mammalian patient. Preferably, the duodenoscope 50 is guided until
its opening 52 is in close proximity to the papilla of Vater 56 and
the sphincter of Oddi 58 which lead to the common bile duct and the
pancreatic duct 60. As such, the advancing step includes passing
the wire guide 20 and access device 40 as a unit through the
working channel of the duodenoscope 50 and through the sphincter of
Oddi 58. The wire guide 20 may then be advanced to provide deep
cannulation of the biliary tree where the tassel tip 30 in the
deployed configuration of the wire guide 20 minimizes the potential
for trauma to the structures of the biliary tree. Finally, the wire
guide 20 may be withdrawn such that the tassel tip 30 again takes
its delivery configuration within the access device 40.
As indicated in the Background section, newer access devices
provide rapid exchange of multiple devices through the provision of
exchange ports formed in a distal portion of the access device. For
example, this exchange port (or side hole) is placed at about 6 cm
from the tip of the catheter or other access device such that only
about 6 cm of the wire guide needs to be placed through the
internal passageway of the device. Thus, the umbrella shape of the
tassel tip 30, which impinges upon the distal end of the access
device when it is withdrawn into its internal passageway, serves as
an additional identifier to the physician of the wire guides'
location. As such, inadvertent disconnection of the wire guide and
access device by withdrawing the wire guide through the exchange
port is further minimized. Preferably, each of the strands 32 of
the tassel tip 30 extend an axial distance much less than 6 cm so
that the tassel tip 30 may be located entirely within working
channel of these new access devices.
Accordingly, it will be recognized by those skilled in the art that
the present invention provides a wire guide and method for
cannulation using the wire guide which assists in procedures such
as ERCP. The wire guide and method minimize the potential for
trauma to the ducts in a biliary tree, especially during deep
cannulation. At the same time, the wire guide and method reduce the
chances of disconnection of the wire guide from newer access
devices which while still providing rapid exchange of such
devices.
The foregoing description of various embodiments of the invention
has been presented for purposes of illustration and description. It
is not intended to be exhaustive or to limit the invention to the
precise embodiments disclosed. Numerous modifications or variations
are possible in light of the above teachings. The embodiments
discussed were chosen and described to provide the best
illustration of the principles of the invention and its practical
application to thereby enable one of ordinary skill in the art to
utilize the invention in various embodiments and with various
modifications as are suited to the particular use contemplated. All
such modifications and variations are within the scope of the
invention as determined by the appended claims when interpreted in
accordance with the breadth to which they are fairly, legally, and
equitably entitled.
* * * * *